The WP Timetics- AI-powered Appointment Booking Calendar and Online Scheduling Plugin plugin for WordPress is vulnerable to Account Takeover/Privilege Escalation via Insecure Direct Object Reference in all versions up to, and including, 1.0.25 via the save() due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to reset the emails and passwords of arbitrary user accounts, including administrators, which makes account takeover and privilege escalation possible.
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.